Drying of non-pulverulent materials.



P. TIBMANN.

DBYING 0F NON-PULVBRULENT MATERIALS.

APPLICATION PII-ED JAN. 11, 1909.

Patented May- 16, 1911 'Drying ot" NonTulverulent Materials UNITED rarnnr OFFICE.

FRITZ TIEMANN, OF BERLIN, GERMANY.

DRYING 0F NON-PULVERULENT MATERIALS.

Specification of Letters Patent.

Patented May 16, 1911.

A i i Application filed January 11, 1909. Serial No. 471,678.

To all whom it may concemu" Be it known that l, Farr?. Tii-inaNN, director, a subject of the German llmperor, residing at 259 Kiirfiirstendanim, Berlin, Germany, have invented certain new and useful"Improvements in or Relating to the and l do hereby declare the followinpr to he a full, clear, and exact description of the iu,- vention, such as will enable others skilled in the art to which it appertains'to malte and use the same. y

In drying non-pulverulent substances with a highproportion of moisture lor use asfueh'such as bagasse or residue ot' cane sugar manufacture, peat and thc like, by

means ot' gases actingdirectlyon the sul` stance to be dried-the serious inconveniente presents itself` that the drying gases, `forced t0 pass through the substance to be dried, soon become saturated with moisture and then,` during Jfurther action, again give ott i such moisture to the said substance. lVhen gases areused at a high temperature and in large quantities, there is the danger that the material to he driedwill become supcrheated and he ignited, and there is also a loss ot heat, as on the one' hand the gases have to leave the apparatus at a high, tem` perature iii order to avoid the giving,r oil of moisture bel'ore-mentioned, and on the other hand, the i'naterials come out from the apparatushot andhave to be cooled.

The objectioiiable 'features described above` are entirely avoided; by the process and apparatus according to this invention.

ln carrying outl the process forming; a.'

part of this invention, the material to be dried is` caused to move downward ina widening column, and a heated dryingl luid such as air or gas is directed transversely against. andthrough the column of materialt so that the latter, as it descends. is continually brought, into contact with `Fresh and unf used air or gases. h i

ln practice, `it .isv advisable to cause the drying1r yerases used to act by passi ng through separate inlets at dill'erent levels and not through a single opening on the whole wall of the material. Tu that way the advaiitage is obtained thatI in case of an accidental `irregula arrangement oll thc material, iii

whole ot' the ,gas does not pass without being!I utilised considerably, while it is also pos sible to use,.at difl'erenty zones, gases of different temperatures, more particularly with temperatures decreasinglfrom the top clownward, while gases of different origin might also he used at ditl'erent zones. i

A constructional form of apparatus for cari-yimgr out the process according to this invention is illustrated by way ot example in the accompanying drawing in which- Fgrure l isha vertical section through the apparatus, and Figui), iS a sideelevation partly in section. t

The drying,r shaft o, the width of which is calculated so that the gases leave the material to betlried. at temperatures above their dew point, is limited at the longitudinal sides l 7; by 'alls constituted by perforated or permeable or impermeable plateso arranged iu louver fashion and inclined inwardly, so that when the material is movin;r downward in the apparatus they do not. oll'er any resistance. The said plates thus contain intermediate spaces through which the heating gases are introduced or discliai; jcd. The transverse sides of the apparatus are closed by solid walls d. The drying sha'l't n widens toward the bottom, that is to say, the longitudinal sides aretarranred with an inclination upwardly and inwardly. Tn that way the material is prevented 'from sticking? inv the apparatus.

The drying shaft, is divided in its longitudinal direction` into several compartments o, n.1,(t2, n?, at, r'bv means of transverse walls c. "lhese walls` can be rnadesolid perforated or olllonvered plates.

Above the shaft n, isarrangcd the 'feed hopper f in which is arranged a conveyer f/ to which the material to be dried is hoisted in any suitable `manner andstrom which it. is distributed among the single compartnicnts ot' the apparatus. Thev shaltfm is closed at the bottom by rolls 7iY h1 adjustabk, relatively to one anotheri Owing to this arrangement` and to the regulation ol the stant discharge ot the material kis regulated.

rlhe conwyer z' arranged.below` the rolls, is used tor cari-yimgr away the dried material.

Drviner frases are supplied to the' apparalus through the side wall L?.` it desired, at dil'crcnt temperatures and of different ori- `ein. 'lo that endpthe lsaid Vall isalivided into vseveral superposed ctanpaitmeiils, of which louir 'are shown in `thc drawing', to which are connected 'funnel `shaped boxes 1'.: 'mI n. These compartments may l'ie'and are preferably still further subdivided in spced with which the rolls move, the eon' compari ment is provided with two funnels).' To the oppositewall b is connected a chiru-l ney 0 through which the used up heating gases and vapors escape.

Drying gases are preferably supplied by means of fans p which are connected to the piping leading to the boxes Z Z: m n.

The material 'to be dried, which is supplied to the shafts a, 0,1, (12,03, c, a through the hopper f will sink slowly as dry material is removed at the bottom by the rolls Il, h1,

material containing a high'proportion of while the conveyer g will distribute fresh material tothe chambers at the top. As the discharge takes place inthe center of the conduit in its longitudinal direction, the material, on sinking, comes close together, so that it is continuously mixed, and the portions which are at the walls come to the center and vice versa. The transverse walls e contribute t0 this mixing action. As the i heating gases are forced transversely through the material as it descends they have to pass only through a comparatively thin layer of material, so that the transmission of heat is i a uniform one. As the gases always pass through material of equal temperature in various equal layers, the material could not be moistened again bygases already saturated With moisture.

The temperature of the gases supplied, is preferably madeto decrease from the to downward, for instance the gases are a mitted into theupper'box la at a temperature of 500 C., into the box Z at300o C., into the box mat 200 C., or they pass through the apparatus in zones situated one below the other, while to the chamber nis supplied `a gas of about'lO()o C. so that the material leaves the apparatus comparatively cool. The wettest material comes, therefore, into contact with the hottest gases, is quickly heated thereby and the evaporationv of the moisture quickly started. As the drying progresses, the material comes into the zones through which pass gases of lower temperature, 1n order finally to leave the apparatus at a comparatively low temperature.

The quantity of gas supplied to the heat ing zone as a whole vis so adjusted that the gases in the chimney o are not completely saturated with moisture, and at least in the chambers le Z m do not escape at a temperature lower than 100.

The regulation of the temperature ofthe gas is'preferably effected by supplying cold air by means of fans, or by using gases of different origin.

By means of the process and apparatus .according to this invention, it is therefore possible to 'carry on the drying 'of material with any temperatures adjusted to suit the degree of moisture of the materfial inthe single drying periods, to avoid any superheating of the material and to utilizeI the gases completely.

What l: claim is v 1. A method for drying nonrpulverulent -material containing a high proportion of moisture, which consists in supporting the material to Imove downward continuously andl -in a Widening column, and directing heated drying fluid transversely against and through -the downwardly moving column so that the latter is continually brought'into contact with fresh and unused drying' fluid.

2. A method for drying non-pulverulent moisture, which consists in supporting the material to move downward continuously in a widening column, directing heated air or gas transversely through the downwardly moving mass, and removing the d ried material continuously4 from the base of the column. f ,n ,f

3. A method for drying non-pulverulent material, Wliichfconsists in causing the ma terial to move continuously downward, and

directing transversely against and through the moving mass Separate air or gas currents successively decreasing in temperature from top to bottom of the series, so that the material is successively brought into. contact with fresh unused air or gasvof' lower and lower temperature.

4. A method lfor drying nonpulverulent material, which consists in supporting the material to move downward continuously in a widening column and causing separately llt conducted air or gas currentsheated to di-" ferent temperaturasA to flow transversely through the descending material, so that as it descends and becomes drier thequantity of material exposed to the action of the air or gas increases, as well as the time of 'edf posure to such air or gas.

5. A method for drying non-pulverulent material, which consists in supporting the material to move downward. continuously in a gradually widening column, directing heated air or gas transversely through the descending material, and continuously removing the dry material from the center of the base of the column'.

6. Apparat-usfor drying non-pulverulcnt Y' material containing a' high in'oliiortion'of moisture comprisinga vertic ally widening from top to bottom, two opposite sides of which are perforate to allow the heated air to pass transversely through the shaft, means for supplyingseparate heated air orgas currents of successively decreasing temperature from top to bottom,

to one perforate side of the shaft, means for exhausting said; currents from the opposite side of the shaft, a feed hopper at the top of tle shaft, and means for withdrawing and removing the dry material arranged below the base of the shaft.

shaft gra'du- 7. Apparatus fordrying nonpulvcrulent material containing a high proportion of moisture, comprisin a vertical shaft two opposite sides of whlch converge toward the top of the shaft and are perforate to allow heated air or gas to Howtransversely throughy the top of the shaft and means for with-` drawing and vremoving the dried' material arranged below the base of the shaft.

8. Apparatus for drying non-pulverulent material containing a high proportion of moisture, comprisin a vertical shaft, two opposite walls of which converge toward the top of the shaft, and are, composed of in- Wardly inclined louvers, two or more superposed compartments in connection with one louvered side of the shaft, means for supplying air or gases heated to different determined temperatures to said compart-` ments, a feed hopper at the top of the shaft and means for discharging and removing the dry material at the base of the shaft.

9. Apparatus for drying nonpulverulcnt material containing a high proportion ol moisture, comprisinvv a vertical shaft, two opposite walls of which converge toward the top,land are composed of inwardly inclined lo'vers, 4two or more supcrposed compartments in connection with one louvered side of the shaft, means for supplying air or gases heated to diil'erent determined temperatures to said compartments, a feed hop per at the top of the shaft, and rollers arran ed below the center of the base of the sha t, and parallel toits louvered sides, to discharge the dried material onto a conveying device, substantially as described.

l0; Apparatus fordryingnonspulverulent material, containing a high proper ion of moisture, comprising a vertical shaft,` two opposite Walls of which converge toward the top, and are composed of inwardly inclined `louvers` and which is divided into two or more chambers by vertical partitions, each of these chambers being in connection 'with la series of air or gas supplying compartments, a feed hopper at the top of the shaft, and means for discharging and removing the dried material, arranged below the base of the shaft, substantially as described.

In testimony whereof I have affixed m'y signature, in presence of two witnesses.

FRITZ TIEMANN. Witnesses:

HENRY Plasma, VOLDEMAR HAUPT. 

